First, and foremost, the genetic architecture of human pigmentation variation is characterized by the reality that most of the variation is due to a handful of loci. In other words, skin color is not monogenic Mendelian, but neither is it highly polygenic in the same fashion as height or IQ, where variation is distributed across so many loci that alleles have nearly an infinitesimal effect size. The small sample sizes and simple methodologies of aught era genomics were sufficient to capture the relatively large effect variants segregating in many populations. A second major aspect to pigmentation genomics is that the pathways seem strikingly conserved across vertebrates. That means that pelage color research could inform human genetics, and vice versa.Some of the most interesting confirmations of the power of loss of function mutations in humans occurred by inducing a similar change in zebrafish! One inference that I think one might take away from this is that ancient human populations likely exhibited variation due to polymorphism around the same set of loci as modern humans.

But, and there’s a big but, is that though the set of loci which are responsible for pigmentation variation across human populations are familiar, finite, and well characterized, the particular mutations responsible within a given locus varies quite a bit. Because derived mutations which result in reduced pigmentation are mostly loss of function all you need to do is “break” the functionality in some manner. Therefore, you might target a regulatory element, or, the exonic sequence itself, but the possibilities are rather numerous. Heather Norton’s publication from 2007, Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians, is still rather relevant. For various reasons the pigmentation of Europeans has been well elucidated. That means that to a great extent the variation in West and South Eurasians more generally (and North Africans) is well understand because most of the same variants seem to be at play. The big lacunae, as pointed out by Norton et al., concerns East Asians. This is a population which is light-skinned, but lacking in the typical set of European “light” alleles.

The title of the post is “white-skinned”, and not “white”, because the conventional understanding is that East Asians are not white. That term is reserved in world-wide usage for people of European descent (or to a lesser extent related peoples, such as Turks) for historical and cultural reasons.

But this is a recent development. From what I am to understand historically the peoples of Northeast Asia did refer to themselves as white in contrast to the browner people of Southeast Asia (in an analogous fashion, the people of West Asia as far east as Afghanistan consider themselves white, in contrast to the black people of South Asia). Additionally, when Europeans first encountered Northeast Asians in large numbers in the 16th century they observed that physically the people of nations such as Japan and Korea were white in color. Only with total domination of the globe by Europeans in the 19th century did the identification of white and European become such as that Northeast Asians were classed among the “colored” peoples (the appellation “yellow” was taken up by early 20th century East Asian intellectuals). But both quantitative empirical evidence and simple visual inspection can remind us that many Northeast Asians are as light in complexion as many Europeans, albeit never as pale as many Northern Europeans.

A new paper in Molecular Biology and Evolution, A genetic mechanism for convergent skin lightening during recent human evolution, goes a major step toward pinpointing what is going on in a functional sense in relation to East Asians. In fact they’re doing what occurred ten years ago for Europeans. First, they’re finding the variant through GWAS, and second, they are confirming through molecular methods and animal models that the variant of interest is actually the causal mechanism. And, they are also attempting to establish a temporal narrative by adducing signatures of selection.

The major finding is that variation on a particular SNP in OCA2 is responsible for differences in pigmentation across many groups in eastern Eurasia. You should remember OCA2, since the region that spans it and HERC2 accounts for the pattern of blue and brown eye variation in Europeans. The SNP, rs1800414, is in the ancestral state in Europe and Africa, but derived in Northeast Asia. The results from the left are from the HGDP browser. The only thing is that I can’t find the SNP on the browser. So I looked for that particular SNP on my own HGDP data sets, and couldn’t find it. The SNP is in ALFRED, and you can see that the results are somewhat different. The HGDP results (which for whatever reason I can’t replicate) show that the derived allele is modal in Northeast Asia, and, that it is present in the New World. In contrast, the ALFRED map shows that the derived allele is modal among more southerly groups (including indigenous non-Han groups in South China), and absent in the New World. The 1000 Genomes has fewer populations, but large sample sizes. The allele frequency in Japan in the 1000 Genomes matches Alfred more than the HGDP results.

All that being said, the general stylized facts are in alignment. The derived allele is common on the eastern coastal region of Eurasia, and nearly absent in Africa, Europe, and West and South Asia. But a curious aspect to me is that in the 1000 Genomes data the allele is nearly as absent in the Bangladeshi samples as it is in other South Asians. In contrast, the derived variant of EDAR, which is diagnostic of East Asian or Amerindian ancestry, is present at 5% frequency in Bangladeshis, about what you would expect assuming the attested levels of gene flow from an East Asian population. While the authors in the above study found that the effect of the allele is additive, it is curious that in the 1000 Genomes there is no variation across Japanese, North and South Chinese, and Vietnamese. The implication is that the average between group differences across these populations has to be due to variation on other loci. The indigenous Dai people in fact had the highest frequency of the derived allele in the 1000 Genomes.

A final issue that is important to note is that the phylogenetic framework the authors are using is probably wrong. The major value-add of this paper is that they include several Austro-Asiatic populations to the data set, and compared individuals phenotypically between the Austro-Asiatic group and among the Han Chinese. Because the supplemental information isn’t online I don’t know which Austro-Asiatic groups they included in China, but there aren’t too many, so one can guess. The main problem though is that they presume these Austro-Asiatic are basal to the Han. This probably isn’t true. Rather, there was probably a migration of early rice farmers from what is today China proper southward, that resulted in the spread of the Austro-Asiatic languages to Southeast Asia and further west toward India. Vietnamese and Cambodian are two numerous languages which are Austro-Asiatic. Bringing together all the genomic evidence, it seems that a substantial minority of the ancestry of these Austro-Asiatic people are from the descendants of hunter-gatherers who were resident in Southeast Asian during the Pleistocene, but the majority of their ancestry derives from farmers who pushed south.

These details matter because the authors estimated how deep the selection sweeps around this locus must be in terms of time. Using two methods they arrive at a figure between 10 and 15 thousand years (one method is closer to 10, another to 15). That implies that selection began before the Holocene. The interpretation the authors put on these results is that the northern East Asian groups experienced selection as they migrated up from Southeast Asia during the Pleistocene, with the Austro-Asiatic groups being basal and reflecting the ancestral state. The problem, as I suggest above, is that the Austro-Asiatic populations are a compound of genuinely basal groups (their minority ancestry) to the Northeast Asians, and a population to which other Northeast Asians further north may be basal!

One thing Eight thousand years of natural selection in Europe tells us using ancient DNA that a history of admixture is important to understanding the specific dynamics of selection. Though the haplotype based methods were roughly correct, they did not exhibit the granularity necessary to make fine-grained inferences, and did not totally predict what the empirical ancient DNA is telling us about allele frequencies across time. For example, earlier attempts to infer the selection sweep which resulted in high frequencies of SLC45A2 in Europe arrived at a figure a bit north of ~10,000 years. But it seems that a great deal of selection on this locus has been occurring more recently than 5,000 years.

And on a final note, I would point out that the intermediate frequencies of the derived allele in much of East Asia are suggestive to me that the genuine target of selection here is not skin color, but a dominant trait. The fact that the derived allele is nearly absent in Bangladeshis indicates that either the sweep up in frequency is very recent, so that not all East Asian populations experienced it, or, more likely to my mind, there is constraining selection on the trait which is the genuine target of interest in other genetic backgrounds. To decrypt what I’m saying, the derived allele is probably useful in East Asia, but entails some cost. South Asians may already have another allele which gains the same function, and so the cost resulted in purification of the derived allele in Bangladeshis (who are ~10% derived from a group very similar to the Dai).

As should be clear, this paper has some confusions. But it’s a taste of things to come. There are many Chinese who are interested in the genomics of their region, and ancient DNA should begin to unveil the past in the next few years.

greg floated that hypothesis re: humans back in 2007 to me. it hasn't panned out. ie pigmentation alleles don't correlate behavioral variation within populations in humans from what we can see in the studies (the % frequency in NE asians at oca2 for this snp is such that lots of families will have siblings with alternative homozygote states, so it should be obvious). there was earlier work on blue vs. brown eyed europeans, but later work does not seem to be robust (jason malloy looked in NLSY).

so i actually don't know what the target is. i'm just suggesting it might exhibit dominant expression.

"suggestive to me that the genuine target of selection here is not skin color, but a dominant trait."

"the genuine target of interest"

Very coy. ;-)

https://www.youtube.com/watch?v=-L58NPPQ5eI

Any comment?

greg floated that hypothesis re: humans back in 2007 to me. it hasn’t panned out. ie pigmentation alleles don’t correlate behavioral variation within populations in humans from what we can see in the studies (the % frequency in NE asians at oca2 for this snp is such that lots of families will have siblings with alternative homozygote states, so it should be obvious). there was earlier work on blue vs. brown eyed europeans, but later work does not seem to be robust (jason malloy looked in NLSY).

so i actually don’t know what the target is. i’m just suggesting it might exhibit dominant expression.

So I read the entire thing, and these article tend to be technical, but I still have not seen the “why” answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

What does the origin of Han have to do with any of this?
Han Chinese were not widely distributed just 2000 years ago but there were other North EastAsians with pretty much the same characteristics as today.

I'm sure it happened some times but I think the very low population densities during these early turnovers may have meant small populations could be absorbed without much visible trace (even if there is an invisible one).

'Genocide' is a rather loaded word for what may have been selective breeding and resource allocation, if elites tend to have more surviving children and are targeted for marriage by non-elites the effect over time will be that fewer and fewer non-elites exist in an undiluted state. There need not have been a deliberate 'ethnic cleansing', much less actual murderous intent, to explain why ethnicities fade from existence like any other uncompetative animal strain.

According to ALFRED Hazaras despite having much more East Asian ancestry than most Indian groups have no SLC45A2, but Iranians do, and actually in higher frequencies than Bengalis. 1kGenomes (PEL is highly Amerindian) and ALFRED agree that it’s absent in the New World. Perhaps in non-Turkic Siberians as well. Interesting distribution.

Asians tan much more easily than whites, and the tan fades way more slowly. I’ve always wondered what that was about. Peasants or fishermen in China, even in the north, can be permanently dark. You’d never notice they are light skinned until you see their daughters.

Yes, I've noticed this as well. Although there do seem to be some Asians who burn and get red and peel.

What's also interesting is the variation among northern Europeans. They're very pale, but some of them, specifically from the British Isles, seem to be unable to tan and burn easily, while others such as some Germans and Scandinavians seem to be tan very well.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

I’d say recent genetic evidence suggests that if there were Papuan/Aboriginal-like people in East Asia, they were rather absorbed into modern East Asians than genocided.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

What does the origin of Han have to do with any of this?
Han Chinese were not widely distributed just 2000 years ago but there were other North EastAsians with pretty much the same characteristics as today.

According to ALFRED Hazaras despite having much more East Asian ancestry than most Indian groups have no SLC45A2, but Iranians do, and actually in higher frequencies than Bengalis. 1kGenomes (PEL is highly Amerindian) and ALFRED agree that it's absent in the New World. Perhaps in non-Turkic Siberians as well. Interesting distribution.

To decrypt what I’m saying, the derived allele is probably useful in East Asia, but entails some cost. South Asians may already have another allele which gains the same function, and so the cost resulted in purification of the derived allele in Bangladeshis (who are ~10% derived from a group very similar to the Dai).

The infants of many species are light skinned, and human babies are too; at their most helpless age they have a special smell that may serve, with light skin, a provisioning and care eliciting purpose.

Many light skinned female celebrities are heavily tanned and Europeans girl who go clubbing (ie may be trying to elicit male lust) are often to most concerned to not look pale. They look bronzed, practically non European, to look sexy

If there is a cost, and north Asian men are less light-skinned than North Asian women, one might speculate that the cost impacts on men not women. Moreover if this difference appears at puberty it would seem reasonable to guess that eliciting provisioning and care of mother and child in a monogamous mating system may be at at the bottom of it. If so that would predict that polygynous peoples are darker than monogamous ones, which there seems to be a bit of definite tendency for.

http://www.unz.com/pfrost/a-hair-color-allele-of-neanderthal/ [...] Or perhaps that diversity was initially functional and then gradually ceased to be functional … because of some other selection pressure? Perhaps, at the end of the last ice age, there was some non-black hair among northern Asians, though much less than among Europeans. Being less common and thus less normal, and no longer favored by intense sexual selection, there may have been stronger social selection to eliminate deviant hair colors.

Peter suggested the north Asians having multiple hair alleles that were not phenotypically expressed meant there could have been been selection against some once existing diverse hair colours in north Asians.

I suppose lightish skin in a lightish skinned people become polygynous could have been selected against, because it was a disadvantage, perhaps in the men (focus of selection in a polygynous mating system). Were Bangladeshis once very polygynous?

first, could you focus more on your original thoughts bro? cuz you tend to parrot peter a bit too much (i've read his stuff, so i know pretty much all the unoriginal thoughts you dump in the comments).

If so that would predict that polygynous peoples are darker than monogamous ones, which there seems to be a bit of definite tendency for.

there is no evidence of big differences between dark and pale siblings. these are large effect loci segregating in populations. if you can't find it in individual differences then it probably doesn't predict between population differences.

Were Bangladeshis once very polygynous?

no.

the genetic data is now pretty clear that skewed sex ratios (genetic polygyny) is a feature of eurasians over the last 4,000 years, especially west eurasians, including northern europeans. so all the stuff that you are saying above sounds persuasive until you know things (e.g., R1a and R1b).

To decrypt what I’m saying, the derived allele is probably useful in East Asia, but entails some cost. South Asians may already have another allele which gains the same function, and so the cost resulted in purification of the derived allele in Bangladeshis (who are ~10% derived from a group very similar to the Dai).

The infants of many species are light skinned, and human babies are too; at their most helpless age they have a special smell that may serve, with light skin, a provisioning and care eliciting purpose.

Many light skinned female celebrities are heavily tanned and Europeans girl who go clubbing (ie may be trying to elicit male lust) are often to most concerned to not look pale. They look bronzed, practically non European, to look sexy

If there is a cost, and north Asian men are less light-skinned than North Asian women, one might speculate that the cost impacts on men not women. Moreover if this difference appears at puberty it would seem reasonable to guess that eliciting provisioning and care of mother and child in a monogamous mating system may be at at the bottom of it. If so that would predict that polygynous peoples are darker than monogamous ones, which there seems to be a bit of definite tendency for.

http://www.unz.com/pfrost/a-hair-color-allele-of-neanderthal/ [...] Or perhaps that diversity was initially functional and then gradually ceased to be functional … because of some other selection pressure? Perhaps, at the end of the last ice age, there was some non-black hair among northern Asians, though much less than among Europeans. Being less common and thus less normal, and no longer favored by intense sexual selection, there may have been stronger social selection to eliminate deviant hair colors.

Peter suggested the north Asians having multiple hair alleles that were not phenotypically expressed meant there could have been been selection against some once existing diverse hair colours in north Asians.

I suppose lightish skin in a lightish skinned people become polygynous could have been selected against, because it was a disadvantage, perhaps in the men (focus of selection in a polygynous mating system). Were Bangladeshis once very polygynous?

first, could you focus more on your original thoughts bro? cuz you tend to parrot peter a bit too much (i’ve read his stuff, so i know pretty much all the unoriginal thoughts you dump in the comments).

If so that would predict that polygynous peoples are darker than monogamous ones, which there seems to be a bit of definite tendency for.

there is no evidence of big differences between dark and pale siblings. these are large effect loci segregating in populations. if you can’t find it in individual differences then it probably doesn’t predict between population differences.

Were Bangladeshis once very polygynous?

no.

the genetic data is now pretty clear that skewed sex ratios (genetic polygyny) is a feature of eurasians over the last 4,000 years, especially west eurasians, including northern europeans. so all the stuff that you are saying above sounds persuasive until you know things (e.g., R1a and R1b).

It seems to me the fact that men are darker than women AOTBE, (especially easy to see in South Asians I think) makes sexual selection the default assumption.

There is no definite rival hypothesis to Peter's in the post, which is is a bit question marky for the author to be saying Peter's ideas have big holes in them. Lots of what turned out to be good theories have been found unpersuasive before triumphing. This is still at an early stage.

I don't mind parotting someone on a subject in which they are in my opinion correct even if not a widely recognised world authority. Peter is parroting Darwin on sexual selection in humans don't forget.

Another sexually dimorphic characteristic is digit ratio. According to Robert Trivers "In a worldwide sample of peoples, only Finnish people had 2nd : 4th digit ratios as low as Jamaicans."

The lowest digit ratio in the world is found in Denmark, and it seems to me while the Finnish data (and dark skinned Europeans in the Mesolithic) supports the idea that, as you say and contrary to sweeping statements about European monogamy, there was ancient polygyny among Europeans, the low testosteronisation of the Danish population is very odd indeed, and most of western Europe has 2D:4D much closer to the Danes.

Finally women in all times and places seem to have thought their skin tone was something that affects their attractiveness. In bygone day in the west and still in traditional societies light skinned maiden's are the ideal.

In the modern west with societal restraints to sex largely off, men covet bigger muscles to attract women, while women want tanned skin to look sexy. I don't these trends are all cultural, and it is legitimate to draw inferences on evolved propensities.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

So I read the entire thing, and these article tend to be technical, but I still have not seen the “why” answered.

that’s because we don’t know why. do you want me to make stuff up to make you happy?

Asians tan much more easily than whites, and the tan fades way more slowly. I've always wondered what that was about. Peasants or fishermen in China, even in the north, can be permanently dark. You'd never notice they are light skinned until you see their daughters.

Yes, I’ve noticed this as well. Although there do seem to be some Asians who burn and get red and peel.

What’s also interesting is the variation among northern Europeans. They’re very pale, but some of them, specifically from the British Isles, seem to be unable to tan and burn easily, while others such as some Germans and Scandinavians seem to be tan very well.

“The main problem though is that they presume these Austro-Asiatic are basal to the Han. This probably isn’t true. Rather, there was probably a migration of early rice farmers from what is today China proper southward, that resulted in the spread of the Austro-Asiatic languages to Southeast Asia and further west toward India. Vietnamese and Cambodian are two numerous languages which are Austro-Asiatic. Bringing together all the genomic evidence, it seems that a substantial minority of the ancestry of these Austro-Asiatic people are from the descendants of hunter-gatherers who were resident in Southeast Asian during the Pleistocene, but the majority of their ancestry derives from farmers who pushed south”.

Such comments have led to much scorn when I have made them in the past, and so it is great to see agreement here. Of course the southward expansion involved not just the ‘Han’ but earlier groups as well. I think that politics comes into it as Chinese are very unwilling to accept any sort of ancient genetic expansion by any Chinese because many of their neighbours are very nervous about the possibility of such expansion at present.

I agree completely with Shaikorth’s statement regarding Papuan/Australian phenotypes: “they were rather absorbed into modern East Asians than genocided”.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

committed genocide on a massive scale

I’m sure it happened some times but I think the very low population densities during these early turnovers may have meant small populations could be absorbed without much visible trace (even if there is an invisible one).

Yes, I've noticed this as well. Although there do seem to be some Asians who burn and get red and peel.

What's also interesting is the variation among northern Europeans. They're very pale, but some of them, specifically from the British Isles, seem to be unable to tan and burn easily, while others such as some Germans and Scandinavians seem to be tan very well.

Although there do seem to be some Asians who burn and get red and peel.

first, could you focus more on your original thoughts bro? cuz you tend to parrot peter a bit too much (i've read his stuff, so i know pretty much all the unoriginal thoughts you dump in the comments).

If so that would predict that polygynous peoples are darker than monogamous ones, which there seems to be a bit of definite tendency for.

there is no evidence of big differences between dark and pale siblings. these are large effect loci segregating in populations. if you can't find it in individual differences then it probably doesn't predict between population differences.

Were Bangladeshis once very polygynous?

no.

the genetic data is now pretty clear that skewed sex ratios (genetic polygyny) is a feature of eurasians over the last 4,000 years, especially west eurasians, including northern europeans. so all the stuff that you are saying above sounds persuasive until you know things (e.g., R1a and R1b).

It seems to me the fact that men are darker than women AOTBE, (especially easy to see in South Asians I think) makes sexual selection the default assumption.

There is no definite rival hypothesis to Peter’s in the post, which is is a bit question marky for the author to be saying Peter’s ideas have big holes in them. Lots of what turned out to be good theories have been found unpersuasive before triumphing. This is still at an early stage.

I don’t mind parotting someone on a subject in which they are in my opinion correct even if not a widely recognised world authority. Peter is parroting Darwin on sexual selection in humans don’t forget.

Another sexually dimorphic characteristic is digit ratio. According to Robert Trivers “In a worldwide sample of peoples, only Finnish people had 2nd : 4th digit ratios as low as Jamaicans.”

The lowest digit ratio in the world is found in Denmark, and it seems to me while the Finnish data (and dark skinned Europeans in the Mesolithic) supports the idea that, as you say and contrary to sweeping statements about European monogamy, there was ancient polygyny among Europeans, the low testosteronisation of the Danish population is very odd indeed, and most of western Europe has 2D:4D much closer to the Danes.

Finally women in all times and places seem to have thought their skin tone was something that affects their attractiveness. In bygone day in the west and still in traditional societies light skinned maiden’s are the ideal.

In the modern west with societal restraints to sex largely off, men covet bigger muscles to attract women, while women want tanned skin to look sexy. I don’t these trends are all cultural, and it is legitimate to draw inferences on evolved propensities.

It seems to me the fact that men are darker than women AOTBE, (especially easy to see in South Asians I think) makes sexual selection the default assumption.

There is no definite rival hypothesis to Peter's in the post, which is is a bit question marky for the author to be saying Peter's ideas have big holes in them. Lots of what turned out to be good theories have been found unpersuasive before triumphing. This is still at an early stage.

I don't mind parotting someone on a subject in which they are in my opinion correct even if not a widely recognised world authority. Peter is parroting Darwin on sexual selection in humans don't forget.

Another sexually dimorphic characteristic is digit ratio. According to Robert Trivers "In a worldwide sample of peoples, only Finnish people had 2nd : 4th digit ratios as low as Jamaicans."

The lowest digit ratio in the world is found in Denmark, and it seems to me while the Finnish data (and dark skinned Europeans in the Mesolithic) supports the idea that, as you say and contrary to sweeping statements about European monogamy, there was ancient polygyny among Europeans, the low testosteronisation of the Danish population is very odd indeed, and most of western Europe has 2D:4D much closer to the Danes.

Finally women in all times and places seem to have thought their skin tone was something that affects their attractiveness. In bygone day in the west and still in traditional societies light skinned maiden's are the ideal.

In the modern west with societal restraints to sex largely off, men covet bigger muscles to attract women, while women want tanned skin to look sexy. I don't these trends are all cultural, and it is legitimate to draw inferences on evolved propensities.

makes sexual selection the default assumption.

that’s stupid. you don’t know enough about evolution to tell me what the ‘default assumption’ should be.

don’t post long-winded follow up comments. they just annoy me with their repetition and lack of concision.

A follow-up here to something I once read, and perhaps you have a link on. Men universally have a preference for lighter-skinned women, both across races and within them. The explanation given is that higher estrogen levels lead to lighter skin color, and that higher estrogen is a signal of female fertility (also, that estrogen suppresses the growth of the long bones in the legs, making diminutive size also an element of sexual selection.) it was perhaps a Sailer article that linked me to an article showing identical pictures of the same person, but one was darker than the other, and so the dark photo looked male and the light photo female.

Is this understanding of mine incorrect? Do you perchance have a recall of where I might find the demonstration of lighter/darker photos?

that's stupid. you don't know enough about evolution to tell me what the 'default assumption' should be.

don't post long-winded follow up comments. they just annoy me with their repetition and lack of concision.

Thanks for all you do to bring these issues to light, Razib.

A follow-up here to something I once read, and perhaps you have a link on. Men universally have a preference for lighter-skinned women, both across races and within them. The explanation given is that higher estrogen levels lead to lighter skin color, and that higher estrogen is a signal of female fertility (also, that estrogen suppresses the growth of the long bones in the legs, making diminutive size also an element of sexual selection.) it was perhaps a Sailer article that linked me to an article showing identical pictures of the same person, but one was darker than the other, and so the dark photo looked male and the light photo female.

Is this understanding of mine incorrect? Do you perchance have a recall of where I might find the demonstration of lighter/darker photos?

you need to update a bit. turns out these universal preferences for women who are light-skinned and have the 0.7 waist:hip ratio really is robust in stratified societies. i think that there's something cognitively that has to do with neoteny preference at work here, but it really doesn't seem to be a strong effect when you look at the hadza hunter-gatherers (to give an example).

A follow-up here to something I once read, and perhaps you have a link on. Men universally have a preference for lighter-skinned women, both across races and within them. The explanation given is that higher estrogen levels lead to lighter skin color, and that higher estrogen is a signal of female fertility (also, that estrogen suppresses the growth of the long bones in the legs, making diminutive size also an element of sexual selection.) it was perhaps a Sailer article that linked me to an article showing identical pictures of the same person, but one was darker than the other, and so the dark photo looked male and the light photo female.

Is this understanding of mine incorrect? Do you perchance have a recall of where I might find the demonstration of lighter/darker photos?

Thanks.

you need to update a bit. turns out these universal preferences for women who are light-skinned and have the 0.7 waist:hip ratio really is robust in stratified societies. i think that there’s something cognitively that has to do with neoteny preference at work here, but it really doesn’t seem to be a strong effect when you look at the hadza hunter-gatherers (to give an example).

Thank you for the response. I had Evernoted your article a few weeks back on the Hadza, which I recall as demonstrating in a non-interracial way the effects of high versus low investment male parenting. I will update my references on .7 WHR and light-skin-preference for stratified societies only. Fortunately, the people with whom I have discussed this are exclusively from such societies so I have not inadvertently led them astray about their own worlds.

Your review of The 10,000 Year explosion sent me down an interesting rabbit hole from which I have not yet returned. It is often a struggle to understand your writing, which I have to translate to people who cannot understand MY level of understanding of genetics. (I'd guess you're top 20% of top 20% of top 20% of top 20% of top 20% in the field). I appreciate the links you add to allow self-exploration for those who would seek and learn.

@ Razib Khan: The problem, as I suggest above, is that the Austro-Asiatic populations are a compound of genuinely basal groups (their minority ancestry) to the Northeast Asians, and a population to which other Northeast Asians further north may be basal!

Although how far north. Domestication of rice looks Yunnan-Assam region and looks like Tibeto-Burman clade of languages of which Chinese is one have greatest diversity there. So perhaps not necessarily from north in the sense of anywhere too near the Yellow River? Hard to know much without much in the way of ancient dna (even from pre and post Neolithic North China would be acceptable). Early civilization near the Yellow River does not necessarily imply that it is the origin of the East Asian neolithic or mass migrations movements to further south than Yunnan.

@ Razib Khan: The problem, as I suggest above, is that the Austro-Asiatic populations are a compound of genuinely basal groups (their minority ancestry) to the Northeast Asians, and a population to which other Northeast Asians further north may be basal!

Although how far north. Domestication of rice looks Yunnan-Assam region and looks like Tibeto-Burman clade of languages of which Chinese is one have greatest diversity there. So perhaps not necessarily from north in the sense of anywhere too near the Yellow River? Hard to know much without much in the way of ancient dna (even from pre and post Neolithic North China would be acceptable). Early civilization near the Yellow River does not necessarily imply that it is the origin of the East Asian neolithic or mass migrations movements to further south than Yunnan.

It seems to me the fact that men are darker than women AOTBE, (especially easy to see in South Asians I think) makes sexual selection the default assumption.

There is no definite rival hypothesis to Peter's in the post, which is is a bit question marky for the author to be saying Peter's ideas have big holes in them. Lots of what turned out to be good theories have been found unpersuasive before triumphing. This is still at an early stage.

I don't mind parotting someone on a subject in which they are in my opinion correct even if not a widely recognised world authority. Peter is parroting Darwin on sexual selection in humans don't forget.

Another sexually dimorphic characteristic is digit ratio. According to Robert Trivers "In a worldwide sample of peoples, only Finnish people had 2nd : 4th digit ratios as low as Jamaicans."

The lowest digit ratio in the world is found in Denmark, and it seems to me while the Finnish data (and dark skinned Europeans in the Mesolithic) supports the idea that, as you say and contrary to sweeping statements about European monogamy, there was ancient polygyny among Europeans, the low testosteronisation of the Danish population is very odd indeed, and most of western Europe has 2D:4D much closer to the Danes.

Finally women in all times and places seem to have thought their skin tone was something that affects their attractiveness. In bygone day in the west and still in traditional societies light skinned maiden's are the ideal.

In the modern west with societal restraints to sex largely off, men covet bigger muscles to attract women, while women want tanned skin to look sexy. I don't these trends are all cultural, and it is legitimate to draw inferences on evolved propensities.

Did you mean Danes have a high ratio? That was what the 2005 Bang et al study said.

Anyway, here’s a bunch of national ratios according to Manning et al 2000. Not sure if these differences are really meaningful though.

Did Jeong Yu-Mi have surgery to make her eyes look more Caucasian? I read many years ago that this was a growing trend in China, at least, and it wouldn't surprise me if other countries in the region followed similar fads.

I've often remarked to myself that popular actresses in East Asia these days look more European than your average East Asian. Is it just me?

I made the point last year (or was it two years ago?) on Greg Cochran’s blog that I find it a bit odd that SLC24A5 is more prevalent than simple West Eurasian admixture would suggest in both East Africa and South Asia, but not in Central Asia. This seems to suggest that whatever SLC24A5 actually does (beyond lightening skin), East Asians developed a gene which essentially canceled out the selective advantage. Also that it’s unlikely that the main trait under selection was an additive trait like skin color (or height, or intelligence), as otherwise you’d expect that those with derived versions from both East and West Eurasia would be slightly advantaged.

Your noting that OCA2 is rare in Bangladeshis makes me wonder if the presence of SLC24A5 in South Asians for some reason selects against OCA2 – if somehow the two genes not only don’t work in an additive fashion, but in combination actually reduces fitness. What the reduced fitness would amount to I’m not entirely sure, but there are plenty of modern east/west Eurasian admixed people whom could be used as the basis of a major health study.

This seems to suggest that whatever SLC24A5 actually does (beyond lightening skin) [..]

There is a market for SLC24A5 inhibitors drugs to lightning skin in those who do not have the derived alleles to do it naturally.

I see no reason to assume SLC24A5 "actually" does something beyond influencing the pigmentation of skin . I may do something else but I wouldn't dismiss the possibility that SLC24A5 operates not much differently in humans than it does in zebrafish.

I’ve noticed a curious pattern in Finnish pigmentation.
The regions which have had “South Lappic” hunter gatherers(not to be confused with Saami who are their sons from paleo-Laplandic mothers, it would get a hell of a lot more complex if I tried to explain it better than that) inhabitants in historic, or slightly pre-historic times such as south Tavastia(region directly north of Helsinki) Ostrobothnia(northwest coast) have a higher but still overall low incidence of darker skinned individuals who would stand out in most inland regions settled by tiny groups of southeastern Finnish farmers of a fair stock.
People like to connect dark skin with Gypsies in Finland but I’d say that’s a crackpot theory that can explain no more than the tiniest fraction of cases.

Examples of what I’m talking about are Ostrobothnian Finland-Swedish footballer Tim Sparv, Tavastian Finn Ellen Jokikunnas and North Finn rock star “Andy McCoy” who self-identifies as a Gypsy for the prestige but has no Gypsy ancestry.

I made the point last year (or was it two years ago?) on Greg Cochran's blog that I find it a bit odd that SLC24A5 is more prevalent than simple West Eurasian admixture would suggest in both East Africa and South Asia, but not in Central Asia. This seems to suggest that whatever SLC24A5 actually does (beyond lightening skin), East Asians developed a gene which essentially canceled out the selective advantage. Also that it's unlikely that the main trait under selection was an additive trait like skin color (or height, or intelligence), as otherwise you'd expect that those with derived versions from both East and West Eurasia would be slightly advantaged.

Your noting that OCA2 is rare in Bangladeshis makes me wonder if the presence of SLC24A5 in South Asians for some reason selects against OCA2 - if somehow the two genes not only don't work in an additive fashion, but in combination actually reduces fitness. What the reduced fitness would amount to I'm not entirely sure, but there are plenty of modern east/west Eurasian admixed people whom could be used as the basis of a major health study.

This seems to suggest that whatever SLC24A5 actually does (beyond lightening skin) [..]

There is a market for SLC24A5 inhibitors drugs to lightning skin in those who do not have the derived alleles to do it naturally.

I see no reason to assume SLC24A5 “actually” does something beyond influencing the pigmentation of skin . I may do something else but I wouldn’t dismiss the possibility that SLC24A5 operates not much differently in humans than it does in zebrafish.

Could you go more into the evidence for or against the correlation and perhaps causation between pigmentation and behaviors traits? I understand the late Carelton Coon did some research into this area that seems rather interesting. Rushton did as well but it did not go to explain the mechanisms behind such phenomenon.

I see no reason to assume SLC24A5 “actually” does something beyond influencing the pigmentation of skin . I may do something else but I wouldn’t dismiss the possibility that SLC24A5 operates not much differently in humans than it does in zebrafish.

huh? it's a trans-membrane protein. why it has an effect on pigmentation. but mechanistically it is involved in lots of things, as most genes are. i haven't read much about it in relation to humans in terms of variation aside from pigmentation though. (not surprisingly most of the pigment genes seen to involve trans-membrane dynamics because it has a critical role in melanocyte generation).

There is a market for SLC24A5 inhibitors drugs to lightning skin in those who do not have the derived alleles to do it naturally.

maybe. it depends on if africans want to get as brown as i am (i'm a homozyg. derived, but mostly like africans on other loci). the biggest market would be in south asia where you could have people who are het. or even homozy. ancestral who have other skin lightening alleles, so the additive effect could go a long way toward getting brunette white skin.

Could you go more into the evidence for or against the correlation and perhaps causation between pigmentation and behaviors traits? I understand the late Carelton Coon did some research into this area that seems rather interesting. Rushton did as well but it did not go to explain the mechanisms behind such phenomenon.

I see no reason to assume SLC24A5 “actually” does something beyond influencing the pigmentation of skin . I may do something else but I wouldn’t dismiss the possibility that SLC24A5 operates not much differently in humans than it does in zebrafish.

huh? it’s a trans-membrane protein. why it has an effect on pigmentation. but mechanistically it is involved in lots of things, as most genes are. i haven’t read much about it in relation to humans in terms of variation aside from pigmentation though. (not surprisingly most of the pigment genes seen to involve trans-membrane dynamics because it has a critical role in melanocyte generation).

There is a market for SLC24A5 inhibitors drugs to lightning skin in those who do not have the derived alleles to do it naturally.

maybe. it depends on if africans want to get as brown as i am (i’m a homozyg. derived, but mostly like africans on other loci). the biggest market would be in south asia where you could have people who are het. or even homozy. ancestral who have other skin lightening alleles, so the additive effect could go a long way toward getting brunette white skin.

The golden zebra fish has, as far as I know, no particular advantage or disadvantage from its mutated SLC24A5. But supposing a golden mutant had arose among the zebrafish and replaced the original wild type. Zebrafish could tell the difference between the golden mutant and the ancestral type, so the mutant colour might be part of the reason for the mutant gene spreading.

It could be something else but there is no particular reason, as far as I know, to think that light skin could not be an advantage because other people looking could see a difference in the skin, and hence sexual selection cannot be ruled out.

Moreover, we do not know of any casually light coloured coloured skin in people who are resistant to disease. If anything it is quite the opposite (http://www.ncbi.nlm.nih.gov/pubmed/11419954).

Finally maidens in the more traditional societies which prize premarital chastity in a wife in a have often tried to keep their skin as light as possible. In the WEIRD west there is tanning but virginity is not prized in that lifestyle.

you need to update a bit. turns out these universal preferences for women who are light-skinned and have the 0.7 waist:hip ratio really is robust in stratified societies. i think that there's something cognitively that has to do with neoteny preference at work here, but it really doesn't seem to be a strong effect when you look at the hadza hunter-gatherers (to give an example).

Thank you for the response. I had Evernoted your article a few weeks back on the Hadza, which I recall as demonstrating in a non-interracial way the effects of high versus low investment male parenting. I will update my references on .7 WHR and light-skin-preference for stratified societies only. Fortunately, the people with whom I have discussed this are exclusively from such societies so I have not inadvertently led them astray about their own worlds.

Your review of The 10,000 Year explosion sent me down an interesting rabbit hole from which I have not yet returned. It is often a struggle to understand your writing, which I have to translate to people who cannot understand MY level of understanding of genetics. (I’d guess you’re top 20% of top 20% of top 20% of top 20% of top 20% in the field). I appreciate the links you add to allow self-exploration for those who would seek and learn.

I see no reason to assume SLC24A5 “actually” does something beyond influencing the pigmentation of skin . I may do something else but I wouldn’t dismiss the possibility that SLC24A5 operates not much differently in humans than it does in zebrafish.

huh? it's a trans-membrane protein. why it has an effect on pigmentation. but mechanistically it is involved in lots of things, as most genes are. i haven't read much about it in relation to humans in terms of variation aside from pigmentation though. (not surprisingly most of the pigment genes seen to involve trans-membrane dynamics because it has a critical role in melanocyte generation).

There is a market for SLC24A5 inhibitors drugs to lightning skin in those who do not have the derived alleles to do it naturally.

maybe. it depends on if africans want to get as brown as i am (i'm a homozyg. derived, but mostly like africans on other loci). the biggest market would be in south asia where you could have people who are het. or even homozy. ancestral who have other skin lightening alleles, so the additive effect could go a long way toward getting brunette white skin.

The golden zebra fish has, as far as I know, no particular advantage or disadvantage from its mutated SLC24A5. But supposing a golden mutant had arose among the zebrafish and replaced the original wild type. Zebrafish could tell the difference between the golden mutant and the ancestral type, so the mutant colour might be part of the reason for the mutant gene spreading.

It could be something else but there is no particular reason, as far as I know, to think that light skin could not be an advantage because other people looking could see a difference in the skin, and hence sexual selection cannot be ruled out.

Finally maidens in the more traditional societies which prize premarital chastity in a wife in a have often tried to keep their skin as light as possible. In the WEIRD west there is tanning but virginity is not prized in that lifestyle.

The golden zebra fish has, as far as I know, no particular advantage or disadvantage from its mutated SLC24A5.

yeah, you don’t know. if you actually worked in biology you’d kind of have better intuition about these sort of things and not assume that the nearest hypothesis you can think of has to be a default. it’s a loss of function. so if there isn’t an advantage and no functional constraint then it will spread (that’s what happens to cave fish). also, a lot of mutations don’t have huge deleterious effects u can tell immediately (purifying selection can work at lower s).

Moreover, we do not know of any casually light coloured coloured skin in people who are resistant to disease. If anything it is quite the opposite

stop google punditing or i’ll ban you. it’s really obvious what you always do and i’m not amused. i waste a lot of time double checking you when you’re searching for citations to reinforce your priors and it becomes obvious that’s what you did.

yeah, you don’t know. if you actually worked in biology you’d kind of have better intuition about these sort of things and not assume that the nearest hypothesis you can think of has to be a default. it’s a loss of function. so if there isn’t an advantage and no functional constraint then it will spread (that’s what happens to cave fish). also, a lot of mutations don’t have huge deleterious effects u can tell immediately (purifying selection can work at lower s).

My unsupported intuition is that humans can see differences in skin tone in those with a light skin mutation, and it can't be ruled out that visual perception has something to do with the spread of such a mutation.

I'm not arguing that light skin goes with something objective and not in the eye of the beholder

Thank you for the response. I had Evernoted your article a few weeks back on the Hadza, which I recall as demonstrating in a non-interracial way the effects of high versus low investment male parenting. I will update my references on .7 WHR and light-skin-preference for stratified societies only. Fortunately, the people with whom I have discussed this are exclusively from such societies so I have not inadvertently led them astray about their own worlds.

Your review of The 10,000 Year explosion sent me down an interesting rabbit hole from which I have not yet returned. It is often a struggle to understand your writing, which I have to translate to people who cannot understand MY level of understanding of genetics. (I'd guess you're top 20% of top 20% of top 20% of top 20% of top 20% in the field). I appreciate the links you add to allow self-exploration for those who would seek and learn.

naw, i think i need to write more clearly. i don’t know, that takes time and editors….

Dan and Chip Heath in their book Made to Stick talk about the "Curse of Knowledge," where it's hard to remember what it's like to not know. I'm not in any zone with population genetics but you clearly are, and much of what you write goes for a very high-level audience. It's worth striving to understand but you need to be well educated to start with to even approach it.

Feynman had a gift for understanding what it was like not to know, and so could explain topics in language that spanned a lot of experience levels that the top 20% of the population might have had. If you stick with your craft you'll grow into this level of familiarity with both your own knowledge and others' desire to reach across the knowledge gaps separating them from you and speak to all in words they understand. Until you do this, I'll explain as best I can and refer my best learners up the line to people like you. I look forward to your being the Feynman of explaining genetics.

Could you go more into the evidence for or against the correlation and perhaps causation between pigmentation and behaviors traits? I understand the late Carelton Coon did some research into this area that seems rather interesting. Rushton did as well but it did not go to explain the mechanisms behind such phenomenon.

i’ll have to ask greg c again. i don’t have time to look this up right now.

naw, i think i need to write more clearly. i don't know, that takes time and editors....

Dan and Chip Heath in their book Made to Stick talk about the “Curse of Knowledge,” where it’s hard to remember what it’s like to not know. I’m not in any zone with population genetics but you clearly are, and much of what you write goes for a very high-level audience. It’s worth striving to understand but you need to be well educated to start with to even approach it.

Feynman had a gift for understanding what it was like not to know, and so could explain topics in language that spanned a lot of experience levels that the top 20% of the population might have had. If you stick with your craft you’ll grow into this level of familiarity with both your own knowledge and others’ desire to reach across the knowledge gaps separating them from you and speak to all in words they understand. Until you do this, I’ll explain as best I can and refer my best learners up the line to people like you. I look forward to your being the Feynman of explaining genetics.

Yes, Celts have less melanin, are often pinker, burn easily and get skin cancer at higher rates than even other white, ethnic, groups.

Asians, also, do not worship the sun and often protect themselves from the rays with clothing and even umbrellas a la southern belles. At my optometrist's clinic (it is all Chinese) one hot summer day, one of the Chinese receptionists looked horrified at my exposed, tanned skin and said, "It is very hot outside. You should wear umbrella!" All I could picture was one of those multicolored umbrella hats. Not my style, at all.

Part of that is just a difference in skin pigment between the comparison groups, as East Asians are more similar in pigmentation to people from Turkey or Armenia than to European Americans. However, I still think the skin rate of melanoma is still higher in Turkey than most East Asian countries (e.g. my impression is incidence of melanoma in Turkey is like 1/4 of West Europe, then East Asian 1/2 Turkey).

It could be the different mutations themselves, or other mutations background. Ideally the best you could do is probably use an association study on a large sample of Uyghur folks.

The golden zebra fish has, as far as I know, no particular advantage or disadvantage from its mutated SLC24A5.

yeah, you don't know. if you actually worked in biology you'd kind of have better intuition about these sort of things and not assume that the nearest hypothesis you can think of has to be a default. it's a loss of function. so if there isn't an advantage and no functional constraint then it will spread (that's what happens to cave fish). also, a lot of mutations don't have huge deleterious effects u can tell immediately (purifying selection can work at lower s).

Moreover, we do not know of any casually light coloured coloured skin in people who are resistant to disease. If anything it is quite the opposite

stop google punditing or i'll ban you. it's really obvious what you always do and i'm not amused. i waste a lot of time double checking you when you're searching for citations to reinforce your priors and it becomes obvious that's what you did.

yeah, you don’t know. if you actually worked in biology you’d kind of have better intuition about these sort of things and not assume that the nearest hypothesis you can think of has to be a default. it’s a loss of function. so if there isn’t an advantage and no functional constraint then it will spread (that’s what happens to cave fish). also, a lot of mutations don’t have huge deleterious effects u can tell immediately (purifying selection can work at lower s).

My unsupported intuition is that humans can see differences in skin tone in those with a light skin mutation, and it can’t be ruled out that visual perception has something to do with the spread of such a mutation.

I’m not arguing that light skin goes with something objective and not in the eye of the beholder

Do you think the fact that East Asians have a lower rate of skin cancer than Europeans is related to their different pigmentation variants?

http://www.cdc.gov/cancer/skin/statistics/race.htm

Yes, Celts have less melanin, are often pinker, burn easily and get skin cancer at higher rates than even other white, ethnic, groups.

Asians, also, do not worship the sun and often protect themselves from the rays with clothing and even umbrellas a la southern belles. At my optometrist’s clinic (it is all Chinese) one hot summer day, one of the Chinese receptionists looked horrified at my exposed, tanned skin and said, “It is very hot outside. You should wear umbrella!” All I could picture was one of those multicolored umbrella hats. Not my style, at all.

Do you think the fact that East Asians have a lower rate of skin cancer than Europeans is related to their different pigmentation variants?

http://www.cdc.gov/cancer/skin/statistics/race.htm

Part of that is just a difference in skin pigment between the comparison groups, as East Asians are more similar in pigmentation to people from Turkey or Armenia than to European Americans. However, I still think the skin rate of melanoma is still higher in Turkey than most East Asian countries (e.g. my impression is incidence of melanoma in Turkey is like 1/4 of West Europe, then East Asian 1/2 Turkey).

It could be the different mutations themselves, or other mutations background. Ideally the best you could do is probably use an association study on a large sample of Uyghur folks.

Culturally in northern China, pale skin is considered as beauty, especially for women. In south Cantonese culture, dark skin can also be considered beauty as 黑美人. But overall in Chinese culture, pale-skin is stereotypically associated with intellectuals, noble class, gentle temperament. Dark skin is stereotypically associated with bravery/aggression/rudeness/underclass. Characters in romance of three kingdoms exemplify this stereotype. Dark guys often take roles of bravery as frontline storming troopers or heroes. Pale guys are brainy planners or rulers. It is unclear whether cultural stereotypical view is result of learning or genetic instinct. If it is learning, then cultural environment might shape sexual selection. If it is instinct, pale skin might be marker for other survival advantage.

In animal world, pale mutation is often associated low light environments like dark caves or deep ocean or polar regions. Due to devolutional nature of pale mutation, pale skin can happen very fast in a few generations. If there is any implication for human from animal mutation, pale skin humans have similar situation. Farmers might spend less time out doors than hunter-gathers out of their caves. Noble class might hereditarily spend less time under the sun than lower classes. Intellectuals did most their work in doors just like today’s world. All these might contribute the development of pale skin. Just hypothesis which need research to find evidences(data).

"Due to devolutional nature of pale mutation, pale skin can happen very fast in a few generations. "

Are you suggesting that (absent chain migration - they tend to bring in a spouse from the old country for obvious reasons) that the Indian/Pakistani population are likely to get paler in the (relatively) low-light UK ?

This Mongolian skin color is also quite common in some northern Chinese village. Northern China bordered with Mongolian geographically(Great wall as dividing line). The difference from northern European is mainly at face color. The body color can be almost identical to northern European.

Historically northern China was also repeatedly settled by waves of northern nomads/hunter(Mongolian/Manchurian types people) and became farmers. This also explained higher diabetes rate of northern Chinese due to ancestors with such low carbohydrate traditional food (meat and dairy mainly).

The major finding is that variation on a particular SNP in OCA2 is responsible for differences in pigmentation across many groups in eastern Eurasia. You should remember OCA2, since the region that spans it and HERC2 accounts for the pattern of blue and brown eye variation in Europeans. The SNP, rs1800414, is in the ancestral state in Europe and Africa, but derived in Northeast Asia.

The northwest and northeast of Eurasia have two groups of indigenous inhabitants, each of which have different pigmentation genes making them white skinned. White skin being for increased vitamin D at high latitude seems to have fell from favour since Norton’s paper, but it makes sense at a very basic level, because:-

The big lacunae, as pointed out by Norton et al., concerns East Asians. This is a population which is light-skinned, but lacking in the typical set of European “light” alleles.

I don’t know much about pleiotropy, but it seems to me Europeans And Northeast Asians both being white skinned as a side effect of the true target of selection (dominant or otherwise) would not explain why Europeans And Northeast Asians are white skinned because of their own particular SNPs on different GENES. Is it likely different genes (dominant or otherwise) for some phenotype (the cryptic target of selection) would have the same side effect?

All right, perhaps the white skinned variant of SLC24A5, a ” derived variant so common across the world today probably spread from the Middle East least than 10,000 years ago” and increased prodigiously in Ethiopia and the Deccan plateau for some reason unconnected with its skin lightening effects. That does not mean that it didn’t become fixed (100%) in Europe for the same reason. And the vitamin D hypothesis is holed below the the waterline by the skin lightening variant of SLC24A5 being selected for in Ethiopia.

I don’t want to get too teleological, but the white skinned Europeans and white skinned north east Asians having the same side effect from different genes for the same cryptic target of selection trait seems less likely that white skin not being a side effect in those cases at least.

So to wind it up (it seems Peter Frost won’t be back, and so I’m quitting commenting too) lighter skin SLC24A5 is suggestive of something other than light skin being the true target of selection for some of the non European spread for that one variant, but to explain the white skinned of Europe and north east Asia it’s still sexual selection versus vitamin D in my book.

but it seems to me Europeans And Northeast Asians both being white skinned as a side effect of the true target of selection (dominant or otherwise) would not explain why Europeans And Northeast Asians are white skinned because of their own particular SNPs on different GENES. Is

genes come in families and pathways. and it's not always in different genes, as this example shows. basically the same set of genes can 'interact' functionality and so be part of the same mutational target.

The major finding is that variation on a particular SNP in OCA2 is responsible for differences in pigmentation across many groups in eastern Eurasia. You should remember OCA2, since the region that spans it and HERC2 accounts for the pattern of blue and brown eye variation in Europeans. The SNP, rs1800414, is in the ancestral state in Europe and Africa, but derived in Northeast Asia.

The northwest and northeast of Eurasia have two groups of indigenous inhabitants, each of which have different pigmentation genes making them white skinned. White skin being for increased vitamin D at high latitude seems to have fell from favour since Norton's paper, but it makes sense at a very basic level, because:-

The big lacunae, as pointed out by Norton et al., concerns East Asians. This is a population which is light-skinned, but lacking in the typical set of European “light” alleles.

I don't know much about pleiotropy, but it seems to me Europeans And Northeast Asians both being white skinned as a side effect of the true target of selection (dominant or otherwise) would not explain why Europeans And Northeast Asians are white skinned because of their own particular SNPs on different GENES. Is it likely different genes (dominant or otherwise) for some phenotype (the cryptic target of selection) would have the same side effect?

SLC24A5 is a a trans-membrane protein that has an effect on pigmentation. and much else so I can see how the variant of SLC24A5 may have spread because of something it does that we cannot see, and the lightening of skin is a side effect . http://www.unz.com/gnxp/slc24a5-has-probably-been-under-selection-in-india/

All right, perhaps the white skinned variant of SLC24A5, a " derived variant so common across the world today probably spread from the Middle East least than 10,000 years ago" and increased prodigiously in Ethiopia and the Deccan plateau for some reason unconnected with its skin lightening effects. That does not mean that it didn't become fixed (100%) in Europe for the same reason. And the vitamin D hypothesis is holed below the the waterline by the skin lightening variant of SLC24A5 being selected for in Ethiopia.

I don't want to get too teleological, but the white skinned Europeans and white skinned north east Asians having the same side effect from different genes for the same cryptic target of selection trait seems less likely that white skin not being a side effect in those cases at least.

So to wind it up (it seems Peter Frost won't be back, and so I'm quitting commenting too) lighter skin SLC24A5 is suggestive of something other than light skin being the true target of selection for some of the non European spread for that one variant, but to explain the white skinned of Europe and north east Asia it's still sexual selection versus vitamin D in my book.

but it seems to me Europeans And Northeast Asians both being white skinned as a side effect of the true target of selection (dominant or otherwise) would not explain why Europeans And Northeast Asians are white skinned because of their own particular SNPs on different GENES. Is

genes come in families and pathways. and it’s not always in different genes, as this example shows. basically the same set of genes can ‘interact’ functionality and so be part of the same mutational target.

basically the same set of genes can ‘interact’ functionality and so be part of the same mutational target

The northeast Asian derived (light skinned phenotype) SNP rs1800414 of OCA2, which remained in the ancestral state in Europe as in Africa, produced white skinned people who don't need derived SLC24A5 to be palefaces.

Mesolithic hunter-gatherers from Spain and Luxembourg had dark skin, yet they had the derived allele of rs12913832 at OCA2, which results in diverse eye colour (grey, green or maybe blue).

My reading is this is not just the same family, it is the same gene but in Europe that quick and simple pathway that worked in northeast Asians to hit the putatively cryptic mutational target (with whiter skin being a side effect) was not taken, even in early European farmers.

Yet before the farmers showed up with light skin SLC24A5 Mesolithic hunter gatherers in Spain and Luxembourg had the SNP at OCA2 for diverse eye colour, which some might consider significantly different to a straightforward SLC24A5 or East Asian OCA2-style loss of skin pigmentation.

It is pretty clear that eyes (monitoring of which is vital for social interaction) altered first and by adding a range of colours to a dark skinned people. I think white skin, even if it may be almost 20,00o years olds as Beleza et al. (2013) and Canfield et al. (2014) estimated, is a later addition to Europeans' appearance, and not due to sexual selection.

Culturally in northern China, pale skin is considered as beauty, especially for women. In south Cantonese culture, dark skin can also be considered beauty as 黑美人. But overall in Chinese culture, pale-skin is stereotypically associated with intellectuals, noble class, gentle temperament. Dark skin is stereotypically associated with bravery/aggression/rudeness/underclass. Characters in romance of three kingdoms exemplify this stereotype. Dark guys often take roles of bravery as frontline storming troopers or heroes. Pale guys are brainy planners or rulers. It is unclear whether cultural stereotypical view is result of learning or genetic instinct. If it is learning, then cultural environment might shape sexual selection. If it is instinct, pale skin might be marker for other survival advantage.

In animal world, pale mutation is often associated low light environments like dark caves or deep ocean or polar regions. Due to devolutional nature of pale mutation, pale skin can happen very fast in a few generations. If there is any implication for human from animal mutation, pale skin humans have similar situation. Farmers might spend less time out doors than hunter-gathers out of their caves. Noble class might hereditarily spend less time under the sun than lower classes. Intellectuals did most their work in doors just like today's world. All these might contribute the development of pale skin. Just hypothesis which need research to find evidences(data).

“Due to devolutional nature of pale mutation, pale skin can happen very fast in a few generations. “

Are you suggesting that (absent chain migration – they tend to bring in a spouse from the old country for obvious reasons) that the Indian/Pakistani population are likely to get paler in the (relatively) low-light UK ?

But I found something opposite for reversed situation.
http://www.omnilogos.com/2015/03/the-evolution-of-cave-life.html

La Cueva Chica population had evolved in 43 years or less into a morphologically intermediate population composed of individuals that were neither totally blind and depigmented nor fully eyed and pigmented.

Cave mosquito (molestus) can become new species in 100 years as shown in this video.

One thing I can answer you in certainty is that we will not see it in our life time. Most animals studied in troglomorphism have much shorter reproductive cycle with a few months or a year. Human reproductive cycle tends to be 20 years or longer. So on time scale, any this depigmentation of human change should take more than 20 time longer time than those cave insects or fish. My estimate should at least be over thousands years.

Human depigmentation might also be involved with other process like downward social mobility from upper noble class. Dark skin underclass could not reproduce themselves due to poor economical conditions. Descendants from pale-upper class replace lost underclass in society. If this is true (actually it is true as evidences provided by Gregory Clark in England), then dark skin underclass simply went extinct slowly over thousands years. If south Asian can not occupied upper class in society, the odd is more likely socially extinction before any chance for genetic change. On the other hand, if they choose to do certain profession immune from social competition, then they will be just like European Gypsy.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

There are aborigines in Taiwan (and maybe on the mainland too) who are supposedly ethnically close to South East Asians.

You can search any SNP allele. They come with references to published data (pop up window).

Or go to Snpedia and key in "Skin color", and you'll get a few Snp, for e.g., SLC24A5 gene, click the allele and it shows which nucleotide is associated with light, dark skinned tone.

Go back to your 23andme, and check which allele you have.

Note:I did mine, and found that my nucleotide is dark skinned. In reality, I'm East Asian guy and my skin tone is even whiter than my White colleagues. So bear in mind that there's no dominant definitive allele that influence the skin color.

but it seems to me Europeans And Northeast Asians both being white skinned as a side effect of the true target of selection (dominant or otherwise) would not explain why Europeans And Northeast Asians are white skinned because of their own particular SNPs on different GENES. Is

genes come in families and pathways. and it's not always in different genes, as this example shows. basically the same set of genes can 'interact' functionality and so be part of the same mutational target.

basically the same set of genes can ‘interact’ functionality and so be part of the same mutational target

The northeast Asian derived (light skinned phenotype) SNP rs1800414 of OCA2, which remained in the ancestral state in Europe as in Africa, produced white skinned people who don’t need derived SLC24A5 to be palefaces.

Mesolithic hunter-gatherers from Spain and Luxembourg had dark skin, yet they had the derived allele of rs12913832 at OCA2, which results in diverse eye colour (grey, green or maybe blue).

My reading is this is not just the same family, it is the same gene but in Europe that quick and simple pathway that worked in northeast Asians to hit the putatively cryptic mutational target (with whiter skin being a side effect) was not taken, even in early European farmers.

Yet before the farmers showed up with light skin SLC24A5 Mesolithic hunter gatherers in Spain and Luxembourg had the SNP at OCA2 for diverse eye colour, which some might consider significantly different to a straightforward SLC24A5 or East Asian OCA2-style loss of skin pigmentation.

It is pretty clear that eyes (monitoring of which is vital for social interaction) altered first and by adding a range of colours to a dark skinned people. I think white skin, even if it may be almost 20,00o years olds as Beleza et al. (2013) and Canfield et al. (2014) estimated, is a later addition to Europeans’ appearance, and not due to sexual selection.

I think white skin, even if it may be almost 20,00o years olds as Beleza et al. (2013) and Canfield et al. (2014) estimated, is a later addition to Europeans’ appearance, and not due to sexual selection.

i agree that it is hard to imagine if modern gen. arch. correct how white skin can be that old. part of the issue with inferring from haplotype structure is that they have naive models of pop structure, and i think the pop structure (admixture) is really confounding stuff.

My reading is this is not just the same family, it is the same gene but in Europe that quick and simple pathway that worked in northeast Asians to hit the putatively cryptic mutational target (with whiter skin being a side effect) was not taken, even in early European farmers.

Yet before the farmers showed up with light skin SLC24A5 Mesolithic hunter gatherers in Spain and Luxembourg had the SNP at OCA2 for diverse eye colour, which some might consider significantly different to a straightforward SLC24A5 or East Asian OCA2-style loss of skin pigmentation.

OCA2-HERC2 has pigmentation effects aside from eye color, it is just tissue specific in having a very large effect size there. but it correlates with lighter hair and skin too in some literature, just not that much. that is a fact and obvious if you read the papers.

basically the same set of genes can ‘interact’ functionality and so be part of the same mutational target

The northeast Asian derived (light skinned phenotype) SNP rs1800414 of OCA2, which remained in the ancestral state in Europe as in Africa, produced white skinned people who don't need derived SLC24A5 to be palefaces.

Mesolithic hunter-gatherers from Spain and Luxembourg had dark skin, yet they had the derived allele of rs12913832 at OCA2, which results in diverse eye colour (grey, green or maybe blue).

My reading is this is not just the same family, it is the same gene but in Europe that quick and simple pathway that worked in northeast Asians to hit the putatively cryptic mutational target (with whiter skin being a side effect) was not taken, even in early European farmers.

Yet before the farmers showed up with light skin SLC24A5 Mesolithic hunter gatherers in Spain and Luxembourg had the SNP at OCA2 for diverse eye colour, which some might consider significantly different to a straightforward SLC24A5 or East Asian OCA2-style loss of skin pigmentation.

It is pretty clear that eyes (monitoring of which is vital for social interaction) altered first and by adding a range of colours to a dark skinned people. I think white skin, even if it may be almost 20,00o years olds as Beleza et al. (2013) and Canfield et al. (2014) estimated, is a later addition to Europeans' appearance, and not due to sexual selection.

I think white skin, even if it may be almost 20,00o years olds as Beleza et al. (2013) and Canfield et al. (2014) estimated, is a later addition to Europeans’ appearance, and not due to sexual selection.

i agree that it is hard to imagine if modern gen. arch. correct how white skin can be that old. part of the issue with inferring from haplotype structure is that they have naive models of pop structure, and i think the pop structure (admixture) is really confounding stuff.

OK, talking about “my reading” is a bit pompous unless I actually interpret the papers myself, which I can’t .

From reading this post I have found out that a north east Asian specific SNP at OCA2-HERC2 is central to why north east Asians are white skinned. You have made the point several times before that there is support for the diverse eye SNP at OCA2-HERC2 found in Europeans being associated with general lightening of skin and hair , though it is not a very effective mutation in lightening skin .

However this post’s big news has some bearing on your aforementioned killer argument against the significance of eye diversity in Europeans. You informed us that East Asian have their own mutation at OCA2-HERC2 that so powerfully hits the depigmentation pathway that it plays a major role in east Asians being white skinned.

One wonders why in East Asians an SNP of OCA2-HERC2 that very effectively depigmented skin has absolutely no effect on eye colour at all, while Europeans’ own derived OCA2-HERC2 SNP has produced some skin depigmentation with a very powerful effect of eye colour diversity. I think it is a bit of an anomaly that there is no diversity or lightening of eye colours in East Asians as a result of their OCA2-HERC2 pathway mediated whiter skin .

"Due to devolutional nature of pale mutation, pale skin can happen very fast in a few generations. "

Are you suggesting that (absent chain migration - they tend to bring in a spouse from the old country for obvious reasons) that the Indian/Pakistani population are likely to get paler in the (relatively) low-light UK ?

To answer your question, I tried to find research publications on troglomorphism. So far I did not find any information regarding generation length needed for the troglomorphic change.

La Cueva Chica population had evolved in 43 years or less into a morphologically intermediate population composed of individuals that were neither totally blind and depigmented nor fully eyed and pigmented.

Cave mosquito (molestus) can become new species in 100 years as shown in this video.

One thing I can answer you in certainty is that we will not see it in our life time. Most animals studied in troglomorphism have much shorter reproductive cycle with a few months or a year. Human reproductive cycle tends to be 20 years or longer. So on time scale, any this depigmentation of human change should take more than 20 time longer time than those cave insects or fish. My estimate should at least be over thousands years.

Human depigmentation might also be involved with other process like downward social mobility from upper noble class. Dark skin underclass could not reproduce themselves due to poor economical conditions. Descendants from pale-upper class replace lost underclass in society. If this is true (actually it is true as evidences provided by Gregory Clark in England), then dark skin underclass simply went extinct slowly over thousands years. If south Asian can not occupied upper class in society, the odd is more likely socially extinction before any chance for genetic change. On the other hand, if they choose to do certain profession immune from social competition, then they will be just like European Gypsy.

Gypsy now is confirmed with south Asian ancestry. Their pattern depigmentation in Europe might serve as a clue for you. But their depigmentation might have introgression components.

Further evidence of pigmentation association with light can be found even on animal and human body itself.

Most animals displayed colored back and pale belly due to light exposure on the back side. Just think about body color pattern of fish, birds, mammals

Human cloths should contribute to depigmentation process on the body. For human living in the cold environments that need cloths and shelter for most their life, they should develop paler skin color than people living in relative warm environment even at the same latitude, as shown in the following image.

You can see East Asia and East America exhibit relative paler skin due to cold climate comparing to the relative warmer Western counterparts. Since face is often exposed part of body, this explain relative less pale face for Mongolian and northern Chinese. But my own family members get even paler face than body like European. I can only explain this as result of sheltered life (in-door) for my ancestors.

Human palms often display less pigmentation even for African. This is similar to clothing effect since palm have thicker stratum corneum and stratum lucidum. This thickening is needed for protection against constant friction and touch. But it also brings effect of clothing and thus reduce the need for pigmentation.

There is a paler population in himalayas border north India and south Tibet. Likely explanation is cold climate at extreme elevation, which needs constant clothing and shelter to survive. As result of less exposure to light in shelter and clothes, pale mutation can happens.

Did Jeong Yu-Mi have surgery to make her eyes look more Caucasian? I read many years ago that this was a growing trend in China, at least, and it wouldn’t surprise me if other countries in the region followed similar fads.

I’ve often remarked to myself that popular actresses in East Asia these days look more European than your average East Asian. Is it just me?

Did Jeong Yu-Mi have surgery to make her eyes look more Caucasian? I read many years ago that this was a growing trend in China, at least, and it wouldn't surprise me if other countries in the region followed similar fads.

I've often remarked to myself that popular actresses in East Asia these days look more European than your average East Asian. Is it just me?

Yes, only in modern time. Like fashion, some thing change with more exposure of western culture.

If you look at ancient East Asian painting about beauty, they are quite different from modern standard. But one thing remain same, pale-skin as beauty.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China….

That shouldn’t be surprising since proto-Mongoloid east Asians were an Australoid-derived group.

….intermediate frequencies of the derived allele in much of East Asia are suggestive to me that the genuine target of selection here is not skin color, but a dominant trait.

That leaves me wondering if the “dominant trait” wouldn’t be the low density of skin pores among Mongoloids – around 40 pores/sq in – relative to other populations, around 70 pores/sq in. It has been theorized that it was adaptive to wearing animal skins in cold climates due to greater resistance to skin disease. Similarly, there is a relatively low occurrence of body hair among Mongoloids. Another difference between Mongoloid skin and European skin is the greater uniformity of pigmentation with Mongoloid skin. European skin has more in common with African skin than Mongoloid skin in every way except pigmentation, and even then the similarity between Euro and Mongoloid pigmentation only goes so far.

Another wrinkle on the Mongoloid body hair issue. While most Mongoloids have low body hair, there are rare instances of extremely high body hair among the Chinese. The world's record for body hair is held by a Chinese man. I'm not sure if it occurs equally among men and women. It makes me wonder if the coarseness of Asian body hair made skin health under animal skins more of an issue than with races with finer body hair. More leverage on pores vs flex, leading to more irritation and skin disease.

So I read the entire thing, and these article tend to be technical, but I still have not seen the "why" answered. Surely its simply because the Han people originated from an area with little sunlight and thus lighter skin was beneficial to survival.

I also remember reading somewhere that there are trace amounts of DNA of people similar to the aborigines of Australia in South China, the Han people must have committed genocide on a massive scale because there is clearly no such people in China today, other than perhaps the fact that the south Chinese are slightly darker than the northern ones.

‘Genocide’ is a rather loaded word for what may have been selective breeding and resource allocation, if elites tend to have more surviving children and are targeted for marriage by non-elites the effect over time will be that fewer and fewer non-elites exist in an undiluted state. There need not have been a deliberate ‘ethnic cleansing’, much less actual murderous intent, to explain why ethnicities fade from existence like any other uncompetative animal strain.

....intermediate frequencies of the derived allele in much of East Asia are suggestive to me that the genuine target of selection here is not skin color, but a dominant trait.

That leaves me wondering if the "dominant trait" wouldn't be the low density of skin pores among Mongoloids - around 40 pores/sq in - relative to other populations, around 70 pores/sq in. It has been theorized that it was adaptive to wearing animal skins in cold climates due to greater resistance to skin disease. Similarly, there is a relatively low occurrence of body hair among Mongoloids. Another difference between Mongoloid skin and European skin is the greater uniformity of pigmentation with Mongoloid skin. European skin has more in common with African skin than Mongoloid skin in every way except pigmentation, and even then the similarity between Euro and Mongoloid pigmentation only goes so far.

This at least helps explain why NE Asians often age much better than Euros.

intermediate frequencies of the derived allele in much of East Asia are suggestive to me that the genuine target of selection here is not skin color, but a dominant trait.

Alternative hypothesis or speculation.

Human species are the only animals who have arranged mating or marriage (selective breeding process involving third party) beside domestic animals and plants. Only current liberal societies and primitive tribal societies practice free animal like mating process. Most historical civilizations carry out arranged mating or breeding for human.

In civilized societies, social class/family wealth become very important factor in mating process. As my prior post suggested, upper class/wealthy family are likely spending less time outdoor with better sheltered body from sun. If social class is stable over thousands years, troglomorphic mutation with pale skin likely happen in noble class/wealthy family. So the selection is for family wealth/class. Every family want their offspring to marry up. The pale mutation is passively selected due to its association with upper class/wealthy family who basically were living a cave like life (well sheltered). The true genetic factor causing stratification of social class/wealth is more likely general intelligence(IQ) as shown in today world. Luck and rare non-intelligent talents can bring wealth (like today professional sport athletes). But those non-intelligent related wealth are less likely last very long in family tree. At end, only consistent genetic factor in wealth building is intelligence which is selected indirectly through arranged breeding with gold-digger societies.

So the whole story is like this. Family and women want to secure survival of their offspring in human society through extra material wealth. They want marry any one richer than average (sport star, lucky lottery winner, high professionals, wealthy businessmens, upper classes). Those who can consistent present in rich category through generations are the genetic ones based on intelligence (IQ) and hereditary (noble classes). Theses hereditary rich are likely carry pale mutation which is passively selected on through arranged mating.

Further evidence of pigmentation association with light can be found even on animal and human body itself.

Most animals displayed colored back and pale belly due to light exposure on the back side. Just think about body color pattern of fish, birds, mammals

https://youtu.be/-7E7FTSsbkg

Human cloths should contribute to depigmentation process on the body. For human living in the cold environments that need cloths and shelter for most their life, they should develop paler skin color than people living in relative warm environment even at the same latitude, as shown in the following image.

http://www.pbs.org/wgbh/evolution/library/07/3/images/l_073_04.jpg

You can see East Asia and East America exhibit relative paler skin due to cold climate comparing to the relative warmer Western counterparts. Since face is often exposed part of body, this explain relative less pale face for Mongolian and northern Chinese. But my own family members get even paler face than body like European. I can only explain this as result of sheltered life (in-door) for my ancestors.

Human palms often display less pigmentation even for African. This is similar to clothing effect since palm have thicker stratum corneum and stratum lucidum. This thickening is needed for protection against constant friction and touch. But it also brings effect of clothing and thus reduce the need for pigmentation.

There is a paler population in himalayas border north India and south Tibet. Likely explanation is cold climate at extreme elevation, which needs constant clothing and shelter to survive. As result of less exposure to light in shelter and clothes, pale mutation can happens.

intermediate frequencies of the derived allele in much of East Asia are suggestive to me that the genuine target of selection here is not skin color, but a dominant trait.

Alternative hypothesis or speculation.

Human species are the only animals who have arranged mating or marriage (selective breeding process involving third party) beside domestic animals and plants. Only current liberal societies and primitive tribal societies practice free animal like mating process. Most historical civilizations carry out arranged mating or breeding for human.

In civilized societies, social class/family wealth become very important factor in mating process. As my prior post suggested, upper class/wealthy family are likely spending less time outdoor with better sheltered body from sun. If social class is stable over thousands years, troglomorphic mutation with pale skin likely happen in noble class/wealthy family. So the selection is for family wealth/class. Every family want their offspring to marry up. The pale mutation is passively selected due to its association with upper class/wealthy family who basically were living a cave like life (well sheltered). The true genetic factor causing stratification of social class/wealth is more likely general intelligence(IQ) as shown in today world. Luck and rare non-intelligent talents can bring wealth (like today professional sport athletes). But those non-intelligent related wealth are less likely last very long in family tree. At end, only consistent genetic factor in wealth building is intelligence which is selected indirectly through arranged breeding with gold-digger societies.

So the whole story is like this. Family and women want to secure survival of their offspring in human society through extra material wealth. They want marry any one richer than average (sport star, lucky lottery winner, high professionals, wealthy businessmens, upper classes). Those who can consistent present in rich category through generations are the genetic ones based on intelligence (IQ) and hereditary (noble classes). Theses hereditary rich are likely carry pale mutation which is passively selected on through arranged mating.

The dominant factor selected on is material wealth. This leads to indirect genetic selection of intelligence and pale mutations.

....intermediate frequencies of the derived allele in much of East Asia are suggestive to me that the genuine target of selection here is not skin color, but a dominant trait.

That leaves me wondering if the "dominant trait" wouldn't be the low density of skin pores among Mongoloids - around 40 pores/sq in - relative to other populations, around 70 pores/sq in. It has been theorized that it was adaptive to wearing animal skins in cold climates due to greater resistance to skin disease. Similarly, there is a relatively low occurrence of body hair among Mongoloids. Another difference between Mongoloid skin and European skin is the greater uniformity of pigmentation with Mongoloid skin. European skin has more in common with African skin than Mongoloid skin in every way except pigmentation, and even then the similarity between Euro and Mongoloid pigmentation only goes so far.

Another wrinkle on the Mongoloid body hair issue. While most Mongoloids have low body hair, there are rare instances of extremely high body hair among the Chinese. The world’s record for body hair is held by a Chinese man. I’m not sure if it occurs equally among men and women. It makes me wonder if the coarseness of Asian body hair made skin health under animal skins more of an issue than with races with finer body hair. More leverage on pores vs flex, leading to more irritation and skin disease.

If I have my 23andme results, what would be the best way to find my results for the various genes associated with pigmentation, or anything for that matter?

I remember once you shared (on your twitter?) a gene browser...

Thanks

Go to your 23andme result, browse “Tool” –> “Raw Data”

You can search any SNP allele. They come with references to published data (pop up window).

Or go to Snpedia and key in “Skin color”, and you’ll get a few Snp, for e.g., SLC24A5 gene, click the allele and it shows which nucleotide is associated with light, dark skinned tone.

Go back to your 23andme, and check which allele you have.

Note:
I did mine, and found that my nucleotide is dark skinned. In reality, I’m East Asian guy and my skin tone is even whiter than my White colleagues. So bear in mind that there’s no dominant definitive allele that influence the skin color.

Another wrinkle on the Mongoloid body hair issue. While most Mongoloids have low body hair, there are rare instances of extremely high body hair among the Chinese. The world's record for body hair is held by a Chinese man. I'm not sure if it occurs equally among men and women. It makes me wonder if the coarseness of Asian body hair made skin health under animal skins more of an issue than with races with finer body hair. More leverage on pores vs flex, leading to more irritation and skin disease.

Women have smoother, less hairy skin and they have far less body odour. Chinese women are at an extreme in all those characteristics, which are of little use for a great many purposes.